ERRβ/γ

Treatment of differentiated C2C12 cells with the ERRβ/γ agonist (relative to vehicle) over a 2 to 4 h time period reveals a reproducible and robust increase in the immunoreactivity of the GRα-D isoform. It is observed that MAO-A mRNA expression is significantly increased by treatment with the ERRβ/γ agonist, GSK4716. Furthermore, it is observed that GSK4716 induces the expression of the mRNAs encoding peroxisome proliferator-activated receptor-γcoactivator 1α (PGC-1α) and PGC-1β (key regulator of many metabolic genes) identified as direct coactivators for the ERR family. GSK4716 induces the expression of PGC-1 and genes involved in fatty acid oxidation in concordance with the characterized role of ERRγ in cardiac metabolism. Treatment of primary mouse myotubes with GSK4716, an ERRβ/γ agonist, results in a concerted increase in the expression levels of Ppargc1a , Ppargc1b , and the Esrr genes. Furthermore, Cpt1b , Atp5b , and Idh3 , genes in key mitochondrial pathways, are also induced by GSK4716. Additionally, GSK4716 increases citrate synthase activity and cytochrome c protein levels.